Use of a second guide rod parallel to the lifter core is a relatively new and under-utilized method.
The additional guide rod ensures proper alignment of the sliding base within the ejector plates. It also eliminates the bending stresses that occur as a result of the typical load distribution described within the conventional setup.
The new configuration creates a parallelogram within the ejector plate assembly between the primary lifter core, secondary alignment rod, alignment plate and sliding alignment base. The structurally sound parallelogram eliminates the bending moment that occurs in single-rod systems.
The use of a fixed secondary pin eliminates friction between the secondary pin and the upper alignment plate. The actuating load transferred to the primary lifter core is now centered on the axis of the lifter core and in the same direction as the motion of the core. The reduction in friction and bending moment permits a greater lifter angle, allowing the designer to reduce both the necessary die height and the mold footprint on the platen.
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